Low RDSon Logic CMOS Gate

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C gates

Some measurements of supply current:

For NC7SZ14:

3.3V, 366uA

1MHz:

Cheers

Klaus

Linear assumption, then:

Jon

Jon Kirwan a écrit :

Which seems a lot... Also, the "static" (1210uA) current is way too big.

380pF/4 gates, mean 95pF/gate which is 3 time the Fairchild figure...

The static consumption is unmeaserable (or at least below 1uA)

Regarding the high consumption, they are in parallel, so might be cross con duction from device to device if propagation times are no equal

I'll dig further and post back here

Cheers

Klaus

An interesting thought sprung into my head. The driver sections don't have to have shoot-thru, they can be time staggered all the way back to the basic on-off control. I'll have to implement that in my next H-bridge controller ;-) ...Jim Thompson

If they switch, they have to at least charge node capacitances. If a chip has a narrow specified Vcc range, I guess you can avoid overlap fet conduction, at the cost of speed.

Another requirement with analog switches is low charge/glitch injection, which puts constraints on staggering the drives to the analog switch devices.

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Some of the TinyLogic gates could be used as RF power amps.

One of the hidden gems is the LVDS line receiver. These are essentially r-r comparators with screaming-fast CMOS output stages. They make great RF oscillators. Dirt cheap. SN65LVDS2DBVR and such.

Yep. I designed a couple for Fairchild.

(Portland, ME, division. Wonderful town. The car rental people warm up the car interior before they bring it around to you :-) ...Jim Thompson

Nope, not necessary. Ask Klaus. I sent him my whole chip design... minus customer-identifying information. Of course YOU are not allowed to see it >:-)

Big difference between analog switch needs and those for a 500mA H-bridge. ...Jim Thompson

You have a CMOS gate design with zero node capacitances? I would indeed like to see that.

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Right. AC has a significant and intentional crossover current for speed.

HC does not.

conduction from device to device if propagation times are no equal

Are your input edges fast?

Thanks for the data.

On-chip nodal capacitances are quite small... often in the low femto-Farad range. Where you get hurt is when you drive a pin to the outside world. ...Jim Thompson

Of course the static current is that small. That's why I did put quotes. I meant the Jon_fitted_current_at_frequency_zero ...

conduction from device to device if propagation times are no equal

My thought too.

If you have time, more than 2 frequency points will be interesting because of the big "F=0 current" ...

sink. The tiny logic NL27WZ14 has 600mV drop at 32mA which equates to 18ohm RDS on.

ok to parallel to get lower resistance. Also, it must not have to much crossover shoot-through (so probably schmitt trigger type) and must have low dissipation at high operational frequency (1-10MHz)

I was using that one:

You're right, for the Abs max, but its normal operation range is stated as up to 3.6V

sink. The tiny logic NL27WZ14 has 600mV drop at 32mA which equates to 18ohm RDS on.

be ok to parallel to get lower resistance. Also, it must not have to much crossover shoot-through (so probably schmitt trigger type) and must have low dissipation at high operational frequency (1-10MHz)

These little parts just get better as Vcc goes up.

What's the total node capacitance of a p-fet+n-fet drain pair feeding a p-fet+n-fet gate pair, in something like HC?

Do you mean something like an 'HC04?

I don't know. I'll have to look it up. I last did 'HC' stuff for Motorola/ON-Semi in 1997 when I redid all their logic parts to be compatible with Chartered Semiconductor processing.

It'll be large. 'HC' is basically 0.8um feature size, which makes for huge devices. ...Jim Thompson

I started to look that up, then realized that all the information you need is right there on a 74HC04 data sheet ;-) ...Jim Thompson

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